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SWR, or lack there of...

I just finished my install of my first ham radio. I have quite a bit of experience with CB antennas and SWR so I figured it would be a good idea to check my ham rig. I have an icon I'd-5100 with a comet SBB5 antenna connected with a Comet 5 meter pl-259 cable assembly. Comet claims the antenna is "ground independent" so there is no ground whatsoever. The antenna is basically hanging in free space. It's on a Jeep. I tested using an MFJ -842 SWR meter. I tested both 2m and 70cm using several frequencies on each band. My issue is that the SWR needle never moved at all. Does that sound right? I didn't adjust the "tuned from the factory" antenna at all. There really isn't much of a ground plane to speak of either. I'm worried that my brand new meter might be messed up. Anyone ever experienced this? If all is good then this is the best radio install I've ever done... I'm just not sure I'm buying that...IMG_3790.jpgIMG_3789.jpgIMG_3792.jpg

I read the directions for the meter and you have to divide by 10 on low power. It's actually 5 watts... I was testing on low power. I didn't try it on high power but I'm gonna try that after work today. The Icom doesn't have a meter built-in. From what I'm seeing online, it's not uncommon to have ham antennas be pretty close to swr-free. I'm not sure why that is though... Probably something to do with the fact that this antenna is a real 1/2 wave on 2m and two stacked 5/8 wave on 70cm whereas most cb antennas are closer to 1/8 wave at best. You'd need an 36 foot whip to make a full wave cb antenna so I suppose that makes the ground plane more of a concern and antenna tuning more difficult on cb. I THINK I saw the SWR needle move ever so slightly at some point, but I could have been seeing things. Like I said, this is my first ham rig (just got my ticket 2 weeks ago) so I don't have much experience with setting these things up and what is "normal" for these frequencies. I have never messed with an antenna system that was this "true" out of the box so it kinda threw me...

Yes, I do run a CB on that spring. The two are resonant pretty far apart so I'm not getting any issues with bleed-over, but I need to check SWR with both antennas installed to see if there is an issue with that. I ran around for a few hours with both radios turned on and was talking on ham and CB never noticed. The antennas don't touch so I'm thinking I'm ok. I'm going to get one of those Comet rubberized dual band antennas for off road anyway so that should keep things separated a little better. Around town, I don't run a CB anyway, just the ham. The CB is mainly for trail use so...

That's a good antenna I have one. It has a matching network in the base of it. That's why they typically show low swr. Even when you mount them in bad spots. I once saw one mounted a few inches away from a truck cab on the bed rail. It showed good swr but the install undoubtedly caused RF pattern problems. They really do come pre tuned as well. They need very little metal to work. You have more than enough. HOWEVER do not mount antennas that close together. They will electrically couple and cause problems. You need at least 19inches of separation for 2m vhf. Your setup puts the antennas so close together I would worry about damming both radios. Stick that Cb antenna on your bumper, cowl or windshield frame.